Each chemical bond has a natural OSCILLATING frequency at which the atoms move towards and away from each other. The natural oscillating frequency of a bond Is constant at a given temperature and pressure and is dependent on the relative sizes of the bonded atoms, the geometry of the bonds, and the nature of adjacent bonds. Thus, a unique oscillating frequency is associated with each bond in a molecule, except when geometric symmetry exist. Where such symmetry exists, the symmetrical bonds have the same oscillating frequency.